I have fairly complete records of Fan & Mortar from 2000 through 2011. Here are the numbers for the 2000-2005 active phase (ok, so this is probably more detail than anyone really wanted, but since I had the numbers in front of me, I thought I'd share): First eruption: January 2000 (missing exact date), followed by several intervals of a month or more. July 8-late October: intervals mostly 1-2 weeks October 2000 to June 7, 2001: intervals 3 1/2-14 days June 7, 2001 to April 8, 2003: intervals mostly 3-7 days; longest eruption of the "spring slowdown" in 2002 was only 9d21h38m April 26-June 8: mini-dormancy of 42d19h25m (longest interval of active phase) June 8-December 20: erratic intervals of mostly 4-11 days Dec 20, 2003-January 24, 2004: mini-dormancy of 35d01h14m February 2004: back to shorter intervals March-June: long, erratic intervals of 9-27 days July-August: short, regular intervals of 2 1/2-6 days EXCEPT for the shortest interval of the active phase, 1d15h56m September-October: erratic intervals 2-9 days November 2004-March 2005 : regular intervals 2 1/4-6 1/2 days April-May: spring slowdown, longest interval 16d01h21m June-August 8: regular intervals of 2-6 days August 8: active phase comes to a screeching halt with no warning And, here are the numbers for the 2007-2011 active phase: June 5, 2007: first eruption, interval approximately 22 months June 2007-April 2008: First interval 36 days, then intervals erratic, a few periods of 3-5 day intervals but some much longer ones thrown in (up to 24d April 2008-June 2008: Mini-dormancy of at least 57 days (longest interval of active phase) July 2008-November 2008: intervals mostly 2 1/2-5 1/2 days with a little slowdown in October November 2008-April 2009: not much known, hard to know from occasional washed marker reports April 25-May 31: mini-dormancy of at least 35 days June 2009-December 2010: intervals mostly 3-6 days (longest interval of 2010 spring slowdown: 12d3h34m) January-April 2011: intervals 5-8 days May 3-June ~18: mini-dormancy of ~45-46 days July-October 15: intervals 2 1/2-6 days October 14-15 overnight: last eruption of active phase; hard to tell if there was any warning due to most eruptions occurring at night So, that's more than you ever wanted to know about F&M. The 2007-2011 active phase was a little more erratic than 2000-2005 with several mini-dormancies. But both active phases had extended periods of very regular intervals, and *most* eruptions were preceded by "event cycles." The nature of these evolved over time but thanks to radios, Fan & Mortar were certainly more seeable in the 2000s than ever before. --Tara Cross fanandmortar at hotmail.com > Date: Sat, 17 Dec 2011 23:18:39 -0500 > From: goldbeml at ucmail.uc.edu > To: geysers at lists.wallawalla.edu > Subject: [Geysers] Fan and Mortar history > > Between the season-ending reports that Fan and Mortar looked "broken" and > the lack of washed markers to start the winter, I have a sinking feeling > that they've gone dormant for the time being. > > I've cobbled together an incomplete history of F&M active phases over the > past 25 years. Some of it is personal recollection. Where possible I > have corroborated (or corrected) it using the OFVC logbook data posted > on GOSA's website. > > Dormant 1985-86? > Active 1987-88 > Dormant or very infrequent 1989 (early issues of the Sput would know) > Active 1990-94 > Dormant 1995-June 1996 > Active June 1996-May 1998 > Dormant May 1998-July 2000 > Active July 2000-August 2005 > Dormant August 2005-June 2007 > Active June 2007-October 2011 > > In many of the active years, there is a seasonal period of longer > intervals (sometimes over a month) during the spring high water. > The onset of actual dormancy appears to come at any time, often without > warning (2005 is a good example). > > On the flip side, once eruptions resume the intervals might drop right > away to their normal range. Let's hope that happens again soon. > > Michael Goldberg > michael.goldberg at uc.edu > _______________________________________________ > Geysers mailing list > Geysers at lists.wallawalla.edu > -------------- next part -------------- An HTML attachment was scrubbed... URL: </geyser-list/attachments/20111218/bd7f2410/attachment.html>